As drilling techniques are developed increasingly, complicated wells such as extra-deep wells, horizontal wells and extended reach wells, etc. have become the main direction of oil and gas exploration. In the development process of those types of wells, troubles such as blockage during tripping, low penetration rate, jamming of drilling tool, well wall instability, and reservoir damage, etc. may occur easily. Those troubles are largely resulted from the encounter of mud shale formation during drilling. Owing to a fact that mud shale may be hydrated, swell and dispersed easily in conventional drilling fluids, it is difficult to drill to the effective oil and gas reservoir in some areas; in addition, the reservoir may be damaged and severely contaminated due to formation leakage, so as causing adverse effects to subsequent exploitation of the oil and gas reservoir. Therefore, higher and stricter requirements are imposed on the inhibitory additives in drilling fluids. The development of efficient, environment-friendly, and low-cost inhibitors, lubricants, and reservoir protectants has become the top priority in the development of drilling techniques.
At present, all inhibitors, lubricants, and reservoir protectants developed for water-based drilling fluids domestically and abroad have problems such as complex synthesis process, poor high-temperature resistance, and difficulties in large-scale application.